Electrical connection boxes are used to hold various electronic devices (e.g. fuses) and also serve as connection junction points. In this type of connection box, there are two methods by which the electrical connection is made with the parts mounted in the housing. One such method consists of the use of a busbar having tab terminals. Alternatively, such connections are made using a combination of wires having solderless wire terminals and the busbar. Depending upon the nature of the circuitry, the foregoing methods are used selectively.
With reference to FIGS. 10 and 11, electrical connection boxes 101, 201, having different internal shapes, are used depending upon the particular construction method. However, the external shapes of connection boxes 101, 201 are identical.
As shown particularly in FIG. 10, main case 102 of connection box 101 is provided with a plurality of projecting housings 103. A plurality of partitions 105 divides inner wall 104 into a corresponding number of holding chambers 106. In those holding chambers 106 which have no housings 103 above them, engagement pieces 107 project from inner walls 104. Busbar 108 (shown in broken lines) is formed as a flat plate and carries five upwardly projecting tab terminals 109. Busbar 108 and tab terminals 109 are held in holding chambers 106. There are two openings 110 on busbar 108 which are aligned with engagement pieces 107.
When busbar 108 is inserted into holding chambers 106 from below main case 102 (as shown in FIG. 10), a portion of engagement piece 107 engages opening 110 of busbar 108. As a result, busbar 108 is reliably and firmly mounted in the desired position within connection box 101. Thereafter, the lead terminals of fuses (not shown) are inserted into tab terminals 109 of busbar 108 from above (as shown in FIG. 10) housing 103. This completes the electrical connection between the fuses and busbar 108.
The connection box as shown in FIG. 11 is typical of the second method. In this embodiment, wire terminals 213, mounted on the ends of wires 212, can be inserted into the two holding chambers 206 on the right as shown in FIG. 11. Also, busbar 209 is inserted from below so that its three tab terminals 210 project into the corresponding three holding chambers 206 on the left of the Figure. Busbar 209 is a flat plate wherein openings 211 are aligned with corresponding engagement pieces 207. Approximately semi-circular openings 214, on wire terminals 213, are at positions corresponding to engagement pieces 208.
Busbar 209 is inserted into holding chambers 206 from below (as shown in FIG. 11) main case 202. Engagement pieces 207 engage openings 211, thereby mounting the busbar in the connection box at the desired position. Upon insertion of wire terminals 213 into holding chambers 206 (also from below as shown in FIG. 11), engagement pieces 208 engage openings 214 of terminals 213. Thus, wire terminals 213 are mounted at the desired position in the connection box. The lead terminals of fuses (not shown) are inserted from above (as shown in FIG. 11) housing 203 into tab terminals 210 and wire terminals 213. In this manner, the electrical connection between the fuses on the one hand and busbar 209 and wires 212 on the other is established.
Since connection boxes of the type just described are made with various electronic parts mounted in the housings, it is necessary to design them in accordance with the desired circuitry and the method of connection used. Since the internal designs are different for the two methods, a single connection box cannot be used for both purposes. It is, of course, desirable to be able to have only a single form of the connection box as this provides substantial cost savings in stocking, handling, and assembly.